Atomizer



Aug. 14, 1945. A. H. BAHNsoN, JR v2,382,124

ATOMIZER n Patented Aug.l 14, 1945 UNITED STATES PATENT OFFICE ATOMIZERAgnew TH. Bahnson, Jr., Winston-Salem, N. C. Application June 10, 1942,Serial No.` 446,506

8 Claims.

This invention relates to atomizers and is particularly directed toatomizers of the type employed in humidifying systems. Y

A particular problem in the use of spray nozzles for the atomizing ofliquids in a stream of gaseous fluid such as air is to insure that theflow of liquid is -always stopped when the gas flow ceases orsubstantially decreases. If, for example, in an atomizer used in ahumidifying system the water flow continues after the gas pressure hasceased or has fallen to a low value, or if the Water flow can start inthe absence of the full gas pressure, much damage may result from thedischarge of ineffectively atomized water into the air ducts or into theconditioned spaces. Complicated mechanisms have been proposed for thepurpose of preventing such occurrences, particularly for use when air,or other gaseous fluid, is available at a pressure higher than thepressure of the liquid.

A principal object of the present invention is the provision of a simplecompact atomizer which positively shuts off the flow of liquid wheneverthe pressure of the gaseous fluid supplied to the atomizer falls below apredetermined level.

A further object of the invention is the provision of an atomizer inwhich the flow of liquid is positively controlled by the gaseous fluidpressure supplied to the atomizer.

Another object of the invention is the provision of an atomizer in whichthe liquid flow is controlled by gaseous fluid under a pressure lowerthan the liquid pressure- A still further object of the invention is theprovision of an atomizer in which the liquid flow is controlled by thepressure of the gaseous fluid supplied thereto without the use ofsprings or other resilient members.

The accomplishment of these and other objects and advantages will beapparent from the following description of an illustrative embodiment ofthe principles of the invention With particular reference to theaccompanying drawing in which:

Fig. 1 is a central transverse section through an 1atomizer embodyingthe principles of the invenion;

Fig. 2 is a sectional View on line 2-2 of Fig. 1;

Fig. 3 is a fragmentary central section showing a modified liquidpressure diaphragm in place in the atomizer, and

liquid pressure diafor connecting the air or steam supply pipe to theatomizer. The forward portion of body IIJ is bored to receive waternozzle cap 20, to be described later, and to provide a mixing chamber 33adjacent the Water nozzle, and terminates in a spray opening I0. Theinlet II is preferably provided with' a filter screen I2. I

The dependent skirt portion of body I0 is internally threaded to receivegland nut I3, the projecting portion of which is preferably hexagonal inexternal shape for convenience in assembly and disassembly. Internallythe projecting portion of j,

gland nut I3 is threaded to receive the threaded portion of back cap I4,which has a dependent projection externally threaded to engage asuitable `coupling member (not shown) for connecting a'water pipe to theatomizer. The intermediate portion of cap I4 is preferably hexagonal inexternal shape.

The internally projecting portion of back cap I4 is threaded to receivethe fixed valve stem I5 and inwardly of the threaded portion is bored toprovide a Water passage I6. The lower end of valve stem I5 is bored toprovide a passage I5' from the end thereof into water passage I6.

Concentrically positioned about valve stem I5 is a movable valveassembly comprising water nozzle cap 20, preferably of hexagonalexternal sh'ape, slidably mounted in the bore of body IIJ tto provide anair channel 3U between the nozzle cap 20 and body I Il and bored toreceive the upper end of the valve stem, a gland nut ZI threaded intothe skirt of cap 20 and a gland nut 22 threaded into the skirt of glandnut 2I. The internal bores of gland nuts 2I and 22 are largeI than theexternal diameter of valve stem I5 to provide a water passage frompassage I6 to the annular valve seat 23 formed at the inner end of glandnut 2|.

The valve stem I5 is Vprovided with' an adjustable cap member 24threaded thereon and carrying a sealing disc 25, adapted to engage thevalve seat to close the water passage. An annular ilexible diaphragm 26,advantageously made of neoprene, is engaged adjacent its outer edgebetween opposed shoulders on body I0 and gland nut I3 and adjacent itsinner edge between 'the end of the skirt of water nozzle cap 20 andgland nut 2 I.

A similar annular diaphragm 21, typically of smaller eiective surfacearea than diaphragm 26, is engaged adjacent its outer edge between glandnut I3 and back cap I4, and adjacent its inner edge between gland nuts2|` and 22. The movable valve assembly is hollow and constitutes a partof the liquid passage that is supported by the diaphragms 26, 21 fordisplacement, in accordance with the forces developed by the pressures of the liquid and the gaseous medium within their respective passages. l

A lter screen 28 is preferably positioned in the water passage aroundthe stem I5. A slot 22' is provided in the skirt portion of gland nut 22to provide communication between water .passage I6 and chamber 29adjacent diaphragm 21.

It will be seen that the pressure of water or other liquid chamber .29on Adiaphragm 21 will urge the valve assembly upward along valve stem Ito close the valve while the pressure of air` or other gaseous iluid inchamber 30 on diaV- V phragm 26 will urge the valve assembly downwardalong valve stem I5 to open thevalve. Bysuitably selecting the relativeeffective surface areas of the diaphragms 26, 21, the valve may becaused to open upon the supply to the atomizer of Aany predeterminedgaseous pressure and to close whenever the gaseous pressure falls belowa predetermined point. By providing a diaphragm lof -greater eiTectivearea than the diaphragm 21, the valve can be caused to open .and the:atomizer to operate at v gaseous pressures substantially lower than thepressure -of the liquid supplied tothe atomizer. For example, anatomizer vconstructed as shown in Fig. 1 .ofthe drawing has operatedvery effectively with a water pressure of 25 pounds and an air pressurelof 20 pounds,` To provide for easy adjustment of theatom-tzerforvsatisfactory operation at other air and water pressures,the effective area-of diaphragm 21 may .be readily altered bysubstituting diaphragm assemblies having smaller or larger eiectiveareas.

As .shown in Figs. 3 and 4, thediaphrag-m assembly 21" comprises aflexible annular idisc 3I preferably of neoprene and a metal rimv 32; Inthe form shown by way of illustration, 'the rim 32f-extends fartherinward on the lower, pressureside. of the diaphragm than in thediaphragm 21 shown in Fig. l, thereby reducing the effective area of thediaphragm.

In operation, the liquid entering the .atomizer through passage I5passes through passage I6, va1ve'23 and nozzle 2B whereby it issprayed-into` the stream of gaseous fluid, such las air `or .steamentering the atomizer through .inlet I I and passing through chamber'andpassage 3-0, 4and the resultant :atomized liquid is emitted atopening I0. Upon reduction of .the gas pressure, either lintentionallyor accidentally; below ya predetermined amount, the eiectivevdifferential force acting on diaphragm .'21 will close valve 23 andshut off the supply of liquid.

It will zbe seen that the invention comprises not onlythe specicelements :and embodiments illustrated herein, but broadly yembraces anyatomizcr Y for liquids comprising a liquid nozzle, means providing apassage for liquid from an inlet to .the nozzle, .a mixing chamber.adjacent the nozzle, means providing a passage for gaseous fluid froman Yinlet to the mixing chamber, .al valve in the liquid passage, amember responsive to pressure in the liquid passage between'the inlet:and the mounted in said chambena relatively .stationary valve elementadjustable with respect to said xed `member, a hollow movable membertelescoped mentary valve elements depends upon the pressures exertedupon said flexible diaphragms by the fluids within the respectivepassages.

il2. An atomizer of the type including a shell having outlet means andseparate inlets for liquid and a gaseous medium, means within the shellproviding liquid and gaseous medium passages from the respective inletsto said outlet means, and a valve for the liquid passage including avalve member and a cooperating movable valve member urged .towardsvalve-'open position by pressure in said gaseous mediumpassage,characterized by the fact that Asaid movable Valve member 4is hollow andconstitutes apart .of said 'liquid passage, and said `passage-providingmeans .sa-id atomizer shell comprises a plurality of sections, theliquid and the gaseous medium inlets .being in different shell sections,and the outer edges of said flexible members are clampedbetween'd-iiTerent pairs of sections vof said shell.

5.- In an atomizer, a shell having a liquid inlet and `a gaseous mediuminlet, a mixing chamber within said shell having an loutlet for thedischarge ofthe atomized liquid, a liquid .nozzle slidable in said shelland having .an orifice opening .into said mixing chamber, meansincluding rela .tively movable valve members vproviding :a liquidpassage from said liquid inlet to. said nozzle, at least Aone of saidvalve members :being .movable with said liquid nozzle, means including aflexible :diaphragm forming a gaseous medium chamber open to saidgaseous @medium inlet .and Ito said mixing chamber, and means includinga iiexiblediaphragm yforming a liquid chamber between said liquid .inlet-and said liquid passage;

said Idiaphragms being connected to .said slidable liquid nozzle and thevalve member movable therewith, and the pressures in .said vgaseousmedium Vand liquid chambers tending to displace said liquid .nozzle Iandvassociated valve vmember in opposite directions.

6. lin -an atomizen'the invention as recited in claimf, wherein thediaphragm of said gaseous medium chamber iis of 'larger .effectivefareathan the dipahragm of said liquid chamber, whereby said liquid valve:may be opened by a gaseous mediu-mY oi lowerpressure than .that of theliquid. f '-7. In an atomizer, -a shell including anintermediate sectionbetween and .secured to a lrear cap and a mja-in body, 'said .main .body.having -an axial bore therethrough, said shell having a spray outlet atits forward end and an -'interior mixing space at the forward end :ofthe bore from which spray is Idischarged through 'said outlet, va liquidinlet 'through' the rear Icap, .sa gaseous medium inlet through the wallof the main body and opening into the bore thereof, flexible diaphragmsextending across said shell at opposite ends of said intermediate shellsection, a hollow valve and liquid passage assembly extending throughsaid intermediate shell section and supported for axial movement by saiddiaphragms, liquid nozzle means carried by said movable assembly andopening into said mixing space, said movable assembly carrying a valveelement, and a cooperating relatively stationary valve element supportedwithin said shell for engagement by the valve element of the movableassembly upon axial displacement'of the same towards the forward end ofsaid shell, whereby liquid pressure on the rear face of the rearflexible diaphragm tends to close the valve and pressure on the forwardface of the forward diaphragm tends to open the Valve.

8. In an atomizer, the invention as recited in claim 7, wherein theeffective area of the forward flexible diaphragm is greater than that ofthe rear diaphragm, whereby said assembly may 10 be moved rearwardly toopen the valve by a gaseous medium pressure less than that of theliquid.

AGNEW ,I-I. BAHNSON, JR.

